发变组变压器零序差动保护电流互感器极性校验分析

Polarity Check Analysis of Current Transformer with Zero Sequence Differential Protection for Generator-transformer Unit Transformer

简述工程中常用零序差动保护方法,以某电厂一台1000 MW机组的主变为试验对象,论述了一种利用区外单相接地短路进行极性校验的方法,通过对零序电流的记录与分析,所得结论验证了极性的正确性以及校验方法的有效性。

This paper briefly describes the zero sequence differential protection method commonly used in engineering. Taking the main transformer of a 1000 MW unit in a power plant as the test object, a method of polarity checking using out-of-zone single-phase grounding short circuit is discussed. Through recording and analyzing zero sequence current, the conclusion obtained verifies the correctness of polarity and the validity of the checking method.